gh-115808: Add is_none and is_not_none operators

[ThexXTURBOXx]

This PR adds an is_none operator and an appropriate test.
I hope I did not forget to update/reference it anywhere else.

Fixes #115808

• Issue: Add operator.is_none() #115808

[ghost]

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[Eclips4]

Please, update the documentation for this module (Doc/library/operator.rst)

[ThexXTURBOXx]

@Eclips4 Thank you for the suggestion, updated it accordingly.

[AlexWaygood]

Thanks! In order for this to be merged, it would also need:

• Documentation to be added in Doc/library/operator.rst
• An entry in Doc/whatsnew/3.13.rst
• An additional implementation written in C in https://github.com/python/cpython/blob/main/Modules/_operator.c

Here's the most recent PR that added a new function to the operator module, which you could use as a reference:

• #27888

[bedevere-app]

A Python core developer has requested some changes be made to your pull request before we can consider merging it. If you could please address their requests along with any other requests in other reviews from core developers that would be appreciated.

Once you have made the requested changes, please leave a comment on this pull request containing the phrase I have made the requested changes; please review again. I will then notify any core developers who have left a review that you're ready for them to take another look at this pull request.

[ThexXTURBOXx]

I have made the requested changes; please review again

[ThexXTURBOXx]

I have made the requested changes; please review again

Requested changes were made

[AlexWaygood]

Thanks! This looks pretty good to me now. We'll need to wait a while to see if anybody voices any objections on the issue before we can consider merging this, though.

[ThexXTURBOXx]

No problem, take your time! And thank you very much for your valuable comments. They helped me shape my first PR here such that it fits your needs!

[sobolevn]

Thank you! I have several nitpicks :)

[Eclips4]

Looks very good for me. Good job @ThexXTURBOXx 👍

[bateller]

👍

[ThexXTURBOXx]

Rebased on main

[ThexXTURBOXx]

Rebased on main

[ThexXTURBOXx]

Rebased on main

[ThexXTURBOXx]

Thanks for the comments - fixed!

[Eclips4]

Thanks for the comments - fixed!

Looks good, thanks.

However, what is about is_not_none #115808 (comment)?

I think it should be implemented, and I think that it is okay to do so in this PR, since these things are related.

cc @AlexWaygood @rhettinger

[ThexXTURBOXx]

However, what is about is_not_none #115808 (comment)?
I think it should be implemented, and I think that it is okay to do so in this PR, since these things are related.

You are right. I haven't seen this comment yet. I have also added an appropriate is_not_none function.

[AA-Turner]

If there are no outstanding concerns I'll look to merge this in the next few days (cc @Eclips4 if you have any final comments)

A

[Eclips4]

LGTM. Thanks @ThexXTURBOXx for your efforts!

[ThexXTURBOXx]

You're more than welcome, thanks for the reviews! :)

[AA-Turner]

Thanks all!

A